Activity measurements and Northem blot hybridizations were used to study the temporal and spatial expression of carboxypeptidase I in germinating grains of barley (Hordeum vulgare L. cv Himalaya). In the resting grain no carboxypeptidase I activity was found in the aleurone layer, scutellum, or starchy endosperm. During germination high levels of enzyme activity appeared in the scutellum and in...